It's common practice to use incentive spirometry (IS) post-op to prevent pneumonia, it's also used for lung injury and fever reduction.
I haven't seen any data yet about the use of IS with COVID or prevention, but I believe it reasonable to assume that it could reduce the number of COVID+ developing pneumonia and requiring ventilation.
It's not costly. People can also be taught breathing exercises without the use of equipment.
Is anyone specifically using IS for COVID patients in their hospital? Or have an article to share?